20975980 has 12 divisors (see below), whose sum is σ = 44049600. Its totient is φ = 8390384.

The previous prime is 20975971. The next prime is 20975987. The reversal of 20975980 is 8957902.

It is not an unprimeable number, because it can be changed into a prime (20975987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 524380 + ... + 524419.

It is an arithmetic number, because the mean of its divisors is an integer number (3670800).

Almost surely, 2^20975980 is an apocalyptic number.

20975980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20975980 is an abundant number, since it is smaller than the sum of its proper divisors (23073620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20975980 is a wasteful number, since it uses less digits than its factorization.

20975980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1048808 (or 1048806 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 20975980 is about 4579.9541482421. The cubic root of 20975980 is about 275.7871880488.

The spelling of 20975980 in words is "twenty million, nine hundred seventy-five thousand, nine hundred eighty".